An Effective Neodimium Segregation Coefficient in Neodimium-doped Yttrium-Aluminum-Garnet Crystal Growth by Pulling Method

Abstract

Effective Nd segregation coefficient in the Nd: YAG (Nd-doped Y₃Al₅O₁₂) crystal growth by pulling method was determined precisely over 0∼1.3 atom% Nd concentration range at a 0.6 mm hr^-1 growth rate, Two Nd: YAG crystals (∼20 g) were grown from a large melt (∼1kg). Neodymium concentrations in the crystals and residual melts were estimated by 4orescent X-ray analysis, and a value of 0.21 was obtained as the effective segregation epefficient. Next, the optical absorption coefficient of Nd: YAG crystal at 5889 A absorption peak was measured in order to analyze a small specimen for Nd by optical absorption nleasurements. The optical absorption coefficient of 0.97 mm^-1 atom%^-1 was determined in tills way.
The Nd concentrations, calculated by the segregation coefficient, agreed well with those obtained by optical absorption measurements at 5889 Å for six successively grown Nd: YAG oystals. Therefore, the obtained segregation coefficient, 0.21, was confirmed as a reliable value for the Nd: YAG crystal growth by the pulling method.